Inverter-integrated electric compressors, which integrally incorporate inverter devices, are used as air conditioner compressors installed in electric vehicles, hybrid vehicles, and the like. Such inverter-integrated electric compressors are configured so that high voltage direct current power supplied from a power supply unit installed in the vehicle is converted by an inverter device to three-phase alternating current power of a specified frequency, which is then applied to the electric motor so as to drive the electric motor.
The inverter device comprises a plurality of high-voltage electrical components, such as a coil and a capacitor, constituting a noise-removing filter circuit, a plurality of semiconductor switching elements, such as IGBTs, constituting a switching circuit for converting power, an inverter circuit including the filter circuit and the switching circuit, and a circuit board on which a control circuit of the inverter circuit is mounted, and is used to convert direct current power inputted via a P-N terminal into three-phase alternating current power, and output the three-phase alternating current power from a UWV terminal to the motor. The inverter device is incorporated into an inverter housing section provided on the outer circumference of a housing of the electric compressor, thereby integrating the inverter device into the compressor.
A power source cable for supplying direct current power from a power source to the inverter device, as disclosed, for example, in Patent Document 1, is configured so as to connect via a connector of the power source cable to a connector connection section provided on the inverter housing section side, and from there to the P-N terminal on the control circuit board side via a resin circuit board comprising a direct current power line constituted by a terminal block and a wiring pattern, a filter circuit constituted by an inductor coil and a smoothing capacitor provided on the resin circuit board, a busbar assembly, and the like.
Patent Document 2 discloses an arrangement in which a power source input port formation part is formed on a metal inverter cover for closing off an inverter housing space in which is disposed a circuit board on which are mounted a coil and capacitor for a filter circuit, a metal terminal is resin insert molded at the port formation part to provide an integrated resin power source connector, and a power source cable is connected to the power source connector and anchored to the housing of the inverter cover, thereby connecting the metal terminal of the power source connector to the circuit board. Patent Document 3 discloses an arrangement in which a power converter board is anchored and disposed on an interior surface of a circuit board cover with an elastic member sandwiched therebetween, a coil and capacitor for a filter circuit are disposed on a surface facing a housing, and the lower parts of the coil and condenser are inserted into and disposed in recessions in the housing.